4.0.0

• .NET 6.0 support.
• New class StaticStringMethod, which offers polyfills for static methods of the String class:

static string StaticStringMethod.Create<TState>(int, TState, SpanAction<char, TState>);
static string StaticStringMethod.Concat(ReadOnlySpan<char>, ReadOnlySpan<char>, ReadOnlySpan<char>, ReadOnlySpan<char>);
static string StaticStringMethod.Concat(ReadOnlySpan<char>, ReadOnlySpan<char>, ReadOnlySpan<char>);
static string StaticStringMethod.Concat(ReadOnlySpan<char>, ReadOnlySpan<char>);

• The class StringCreator has been replaced by StaticStringMethod.
• Polyfills for the .NET 6.0 methods String.ReplaceLineEndings() and String.ReplaceLineEndings(String).
• The following methods are marked as obsolete and have replacements in the several ReplaceLineEndings methods now,
  which exactly simulate the behavior of the .NET 6.0 method String.ReplaceLineEndings(String):

NormalizeNewLinesTo(this StringBuilder, ReadOnlySpan<char>);
NormalizeNewLinesTo(this StringBuilder, string?);
NormalizeNewLinesTo(this string, ReadOnlySpan<char>);
NormalizeNewLinesTo(this string, string?);